Problems and trends in the development of dairy livestock in Russia

Abstract

Staphylococci are widespread in the environment, which is facilitated by the duration of their survival on various objects. In this regard, rapid and accurate identification of staphylococcal species is in demand, with the aim to assess their pathogenic properties and prescribe adequate drug therapy. This year, 48 staphylococcal cultures were isolated from the udder secretions of cows (sick with mastitis) from six regional agricultural enterprises and tested for a number of biochemical properties. By the minimum number of tests, including catalase activity, mannitol fermentation and plasma coagulation, isolated cultures were differentiated into coagulase-positive and coagulase-negative ones. According to the research results for S. aureus, the three above-mentioned tests are sufficiently informative to classify them as pathogenic staphylococci. S. intermedius strains are catalase- and coagulase-positive, and with respect to mannitol fermentation, the reaction can be either positive or negative, which requires additional research. In addition to the tests listed above, the presence of hemolytic and DNAse activity was confirmed in strains of pathogenic staphylococci. The use of the reagents set of “Multimicrotests for biochemical identification of staphylococci (“MMT S”)” makes it possible to determine the species belonging of coagulase-negative staphylococci. Determination of biochemical properties of staphylococci isolated during bacteriological analysis makes it possible to identify them and assess their pathogenic properties.